The home of GMT
- Royal Observatory
- Meridian Line
- Multi-lingual audio guide
- Free museums
- Planetarium shows
- Cutty Sark
We're Making Improvements. Until 14 June there will be no lift access to Flamsteed House or the Time and Longitude gallery. The Meridian Line and Gallery will still be accessible via wheelchair. Find out more about accessibility at Royal Museums Greenwich
Stand beneath the magnificent onion dome and marvel at one of the biggest telescopes in the world. Join one of our special Evenings with the Stars and look through the telescope yourself.
The 28-inch Greenwich refracting telescope is the largest of its kind in the UK and the seventh largest in the world. It was built to research double star systems and remained in use until the late 1960s. With the recent addition of a computer-aided guidance system and CCD camera, it continues to work as an excellent visual aid to observing the night sky.
It took eight years to make and was a great success in the Royal Observatory’s programme of double star observations. It rests on a mount built 30 years earlier for a smaller telescope. The telescope tube is over 28 feet (8.5 metres) long and is round at each end but rectangular in the middle. This is because its mount was built for a much smaller telescope, so the middle section of the tube had to be tapered in order to fit. Attached to the outside of the tube are smaller telescopes, used as guides to target an object or to magnify the telescope’s scales. The mount allows the telescope to be rotated on the same axis as the Earth, so it can follow a star from east to west across the sky.
Delve deeper into this fascinating topic